3.7
Safety-related functions
The device is intended for use in personal protective equipment for detecting safety-
related objects in mobile and stationary applications.
To this end, it comes with a variety of safety-related functions.
The device has three interfaces for this purpose via which safety-related states and
measured values can be displayed, depending on the selected safety-related function:
•
Digital outputs
•
Analog current output
•
IO-Link
Compared to safety-related measured values, safety-related states are signals at inter‐
faces that prompt the downstream processing units to respond in a safety-related
manner by initiating or maintaining the safe state in the system.
The device meets the requirements of performance level b (PL b), Category B,
according to EN ISO 13849-1:2015 and performance class B (according to
IEC TS 62998-1:2019). It can be used within its area of application for risk reduction
according to its features.
3.7.1
Distance to object – Safety-related Zone near
This function detects objects below a defined distance threshold (see
3
) during dis‐
tance determination. The signal level LOW indicates the requesting of the safety-related
function, i.e., the active state has been reached. An additional configurable hysteresis
of the switching point (see
4
) provides the necessary tolerance in the switching range
to prevent premature switching back to the inactive state.
Min.
1
Max.
2
3
1
0
4
Figure 5: Distance to object, Safety-related Zone near
1
Minimum distance
2
Maximum distance
3
Switching point: Limit of safety-related zone
4
Hysteresis of the switching point
The safety-related information of this function (request of function yes/no) can be
provided via the digital outputs (signal level Low/High) as well as in the process data via
the IO-Link interface.
Status
Digital output
Status bit (bit 0 or bit 1) in the
IO-Link process data
Active (safety-related)
Low
Logical 0
Deactivated
High
Logical 1
3.7.2
Distance to object – Safety-related Zone far
This function detects objects above a defined distance threshold (see
3
) during dis‐
tance determination. The signal level LOW indicates the requesting of the safety-related
function, i.e., the active state has been reached. An additional configurable hysteresis
of the switching point (see
4
) provides the necessary tolerance in the switching range
to prevent premature switching back to the inactive state.
3
PRODUCT DESCRIPTION
16
O P E R A T I N G I N S T R U C T I O N S | DT35S
8027663//2022-08-04 | SICK
Subject to change without notice